Method and apparatus for degasifying liquids



Nov. 5 1929. w. s. ELLIOTT 1,734,

METHOD AND APPARATUS FOR DEGASIFYING LIQUIDS Filed NOV. 19, 1923 2 Sheets-Sheet l Nov. 5, 1929. w. s. ELLIOTT METHOD AND APPARATUS FOR DEGASIFYING LIQUIDS 2 Sheets-Sheet 2 Filed Nov.

INVENTQR Patented Nov. 5, 1929 v UNITED STATES WILLIAM S. ELLIOTT,-OF PITTSBURGH, PENNSYLVANIA METHOD'AND APPARATUS DEGA SIFYING LIQUIDS Application filed November 19, 1923. Serial No. 675,523.

The present invention relates broadly to liquid treating apparatus, and more particularly to heat exchanging apparatus for eiiecting removal from water of its entrained air and gases. 7

It has heretofore been proposed in the art to which this invention relates to attempt the removal of gases from liquids by passing the'liquids in divided condition over a heat- 10 ing surface. The vapors released from the liquids in passing over such surface have then been drawn upwardly through the entering liquid and removed from the appa ratus. While such a movement of the vapors and gases may be desirable from a standpoint \of heat transfer, in "thattheir heat is-recovered by the entering liquid, it is decidedly 0bjectionable from a 'standpointof degasification. This is particularly true for the reason that the solubility of air-in water is a func tion of the temperature, the. solubility decreasing as the temperature increases. With such an apparatus, therefore, the condensable andnon-condensable gases are brought into contact with the liquid under conditions which are highly effective for reentraining or redissolving the released air in the entering li uid.

In accordance with the present invention,

the objections to such a method are obviated and there is provided an efficient deaerating apparatus in which not only is the heat of the released vapors and gases conserved, but the removal thereof is effected under such I conditions that contamination or aeration of the liquid is notpermitted. v

In the accompanying drawings, I have shown. for purposes of illustration only, one embodiment of the present invention, it being understood that the drawings do not define the limits of my invention as changes in the construction and operation therein disclosed may obviously be made without departing from the spirit of my invention or scope of my broader-claims.v

In the drawings, which are largely diagrammat1c, w

Figure 1 is .a verticalxrsectional view through one form of apparatus constructed in accordance with the invention;

Figure 2 is a transverse sectional view on the line 11-11 of Figure l; and

Figure 3 is a detail view, on an enlarged scale, of a portion of the apparatus.

In carrying out the present invention, there may be provided a separating chamber 2 having in the upper portion thereof a plurality of tubes 3 and in the lower portion a liquid space 4. Intermediate the liquid space and the tube nest is a vapor space 5, preferably 00 containing suitable agitating means, such as baffles or plates 6.

Suitably mounted upon the tubes 3 is a distributing plate or grid 7 having provided therein a lurality of openings 8 preferably in the orm of slots substantially coextensive with the length of the tubes 3. As illustrated in detail in Figure 3, these slots are preferably so arranged that the are adapted to deliver any liquid discharge onto the plate 7 directly onto the crowns of the tubes 3. In this manner the liquid is caused to spread out uniformly in comparatively thin sheets whereby it is effectively broken up to facilitate'heat interchange, as herein- 76 after more fully described.

Located at some convenient point with respect to the chamber 2 is a condenser 9 preferably having the vapor space therein in communication with the vapor space 5 withinv 80 the chamber 2 through one or more vapor con- ,nections 10. WVith an arrangement such as indicated in Figure 2 of the drawings, condensate formed within the condenser may be drained back into the chamber 2, While noncondensable gases, such as air, may be released therefrom by venting to the atmosphere or by positively withdrawing the same by means of a suitable ejecting device 11.

For supplying a cooling medium to the 00 condenser 9, this medium preferablybein the liquid to. be degasified, there is provide an inlet connection 12 having located therein a controlling valve 13. Liquid after passing through the controlling valve enters the tubes 1% withinthe condenser, as understood in the art, and thereafter passes to an outlet connection 15. This outlet connection may be provided with branches 16 and 17 adapted to be controlled by valves 18 and 19, whereby the liquid upon leaving the condenser may be caused to travel through either of the branches 16 or 17 or divided and passed simultaneously through both connections.

' The connection 16 leads to an intake pipe 20 supplying liquidto a nozzle 21 which is preferably constructed to effect an atomization of the liquid escaping therefrom. This may be accomplished by providing the nozzle with a series of openings 22 of suitable shape.

The connection 17, on the other hand, may lead to an auxiliary heater 23 by means of which the liquid leaving the condenser 9 may be further heated before passing to the noz- 'zle 21. The outlet from the heater 23 may lead through a pipe 24 and valve 25 to the intake pipe 20.

In operation, a supply of liquid to be degasified may be led from a suitable source through the valve 13 and condenser 9 to the nozzle 21. This liquid in escaping from the nozzle is finely broken up and in this condition falls upon the plate 7 which further breaks up and distributes the same and de livers it to the tubes 3. These tubes may be heated in any suitable manner as by steam supplied through a connection 26, condensate being removed through a drip connection 2' 7. The liquid in passing over the tubes 8 is heated to a point to eifect the evaporation of a definite percentage of the liquid at the pressure existing within the chamber2. In United States Patent No. 1,497,491, of June 10, 1924, I have disclosed and claimed means for effecting a similar result. Thisresult is highly desirable as I have found that the effective separation of air for uniform results is dependent on the evaporation of a definite percentage of the liquid beingtreated. The vapors released by this evaporation are withdrawn through the vapor connections 10 and pass to the vapor space of the condenser 9. In this manner their heat is utilized for preheating the entering liquid. The non-condensable gases are in turn released or withdrawn from the condenser, as described. w .The 'unevaporated liquid passes through the vapor space 5, being at this time substantially at its maximum temperature, and falls upon the agitating platesfi by means of which it is again broken up to thereby effect the release of any remaining air. This degasifie liquid then collects in the bottom of the chamsupplied liquid.

ac same ber from where it may be withdrawn through an ofitake connection 28.

It is highly desirable to make the supply of entering liquid proportionate to the demands for degasified liquid and to this end I preferably control the valve 13 in the liquid supply connection by the level of the liquid 7 within the chamber 2. This may conveniently be accomplished by means of a float 29. as well understood in the art.

In some cases, where a large tube nest within the separating chamber a may conveniently be employed, it is unnecessary to further preheat the liquid after it leaves the condenser 9. In other cases, however, it may be desirable to materially reduce the heating surface of the tubes 3 and in that case the liquid may be passed from the condenser 9 through the preheater 23 in which it may be substantially heated to its boiling point at the pressure employed. The-tubes 3 would then only impart suiiicient aditional heat to insure the evaporation of an amount of the liquid suflicient to drive off all of the entrained air. In this manner, the cost of the separating chamber 2 and its associated parts can be considerably decreased.

It will be understood that both the con nections 16 and 17 may be provided in a common apparatus for alternate or simultaneous use or that but one connection-selected in accordance with the existing'conditions, may be utilized with each installation.

By providing the vapor offtake connection or connections 10 at a point below the tubes 3, it will be apparent that the vapors are not permitted to pass upwardly into contact with the relatively cooler water discharged by the nozzle 21. They are, however, taken off at substantially the point of maximum temperature of the liquid, this being the point at which the solubility of air in the liquid is at a minimum.

' The advantages of thepresent invention arise from the provision of an apparatus for elfectively heating liquid to effect the release therefrom of the entrained air, and then withdrawing the released gases'without giving them an-opportunity to contaminate the I claim:

1. In apparatus for degasifying liquid, a chamber containing a heating surface and having a space below said surface, means for passing the liquid over saidsurface in a downward direction, and a condenser communicating with said space for condensing the vapors released within the chamber.

2. In apparatus for degasifying liquid, a chamber containing a heating surface and havinga space below said surface, means for passing the liquid over said surface in a downward direction, and a condenser communicatingwith said space for condensing the vapors released within-the chamber, said concommunicating with said space for condens-V denser having means insuring the removal of noncondensable gases therefrom.

In apparatus for degasifying liquid, a chamber containing a heating surface and having a space below said surface, means for passing the liquid over said surface in a downward direction, and a condenser communicating with said space for condensing the vapors released within the chamber, said condenser having an inletconnection for the liquid to be degasified whereby the liquid is-preheated by said vapors. V

4. In apparatus for degasifying liquid, a chamber containing a heatin surface over which the liquid is adapted to ow in a downward direction, there being a space within said chamber below said surface, a condenser ing vapors released in the chamberfa heater receiving condensing liquid from said condenser and further heating the same, and a connection receiving the heated liquid from said heater and delivering the same to said chamber.

5. In apparatus for degasifying liquid, .a chamber containing a heating surface over which the liquid is adapted to flowin a downward direction, there beinga space within said chamber below said surface, a condenser communicating with said space for condensing vapors released in the chamber, a heater receiving condensing liquid from said COIl. denser and further heating the same to substantially the temperature and pressure of said chamber, and a connection receiving the heated liquid from said heater and delivering the same to said chamber.

6. The method of separating gases from liquids, comprising providing a chamber having a heating surface therein, supplying liquid to said chamber at a temperature below the temperature of the heating surface, distributing the liquid over said surface, and withdrawing the vapors and gases from the chamber at a point below that-at which the li uid is distributed:

7. The method of separating gases from liqui s, comprising providing a chamber having a heating surface therein, su plying liquid in broken up condition to sai chamher at a temperature below the temperature of the heating surface, distributing said liquor over the heating surface, and withdrawing the vapors and gases from the chamber at a, point below thatat which the liquid is distributed. I

8. The method of separating gases from liquids, comprising providing a chamber having a heating surface therein, su plying liquid in broken up condition to said eating surface, and withdrawing vapors and gases from said chamber at substantially the point of'maximum temperature therein and at a point below the heating surface.

9.The method of separating gases from -to 'said,chamber, means for distri liquids, comprising providing a heating chamber havin a heating surface therein,

supplying liqui to said chamber and delivertemperature of said tube, meansffor distributing-said liquid over said tubes, and a condenser communicatin with said chamber at a point below the distri uting means.

llnIllfiIl apparatus for-separating gases from liquids, a chamber having heating tubes therein, a liquid connection to supply liquid uting said liquid over said tubes, and a condenser cominunicatin with said chamber below the heating tubest erein;

12. The method of separating gases from roviding a chamber liquids, comprising supplying having a heating sur ace therein,

liquid ,to said chamber and delivering the liquid in broken up condition to said heating surface, and withdrawing the vapors and gases from said chamber at substantially the point ofmaximum temperature therein and at a point below the delivery of liquid tosaid chamber.

13. In an apparatus for separating gasesfrom liquids, achamber having tubes therein, a liquid connection to supply liquid in broken up condition to said tubes, and a gas ofitake connection leading from said chainiber'at substantially the point of maximum temperature thereinand at a point below said liquid connection, there being means cooperating with said gas offtake connection for recovering the heat therefrom.

14. The method of separating gases from liquids, comprisingproviding a chamber having heating meansv therein, delivering liquid to said chamber and to said heating means, andwithdrawing the vapors and gases from iio said chamber at a point where the solubility of the gases in the li uid is at a-minimum.

15. The method 0 separating'gases from liquids, comprisin providing a chamber having a heating sur ace therein over which the liquid isadapted to pass, supplying li uid to said surface in broken upcondition, an withdrawing vapors and gasesfrom said chamber at a point where the solubility of the gases in the liquid is at a. minimum. 16. n apparatus for separating gases from liquids, a chamber havin a heating surface therein over which'theliquid is adapted to p a liquid connection to suppl heated iquid-in broken up conditionto said surface, a vapor and gas ofl'take leading from said chamber at a point where the solubility of the gas in-ther liquid is at a and means cooperating with said ofitalre for im parting the heat of the vapor andgases to the liquid supplied to said chamber.

17. In apparatus for degasifying liquid, a

chamber containing a heating surface and having aspace below said surface, means for supplying a heating medium for heatingsaid surface, means for passing'the liquid to be degasified-oversaid surface in a downward direction for abstract-ing heat therefrom, and

a condenser communicating with said space for condensing the vapors released within said chamber;

18. In the method of treating liquid to effect the-removal of air therefrom, the'steps consisting of supplying liquid to 'a heating means to pro-heat the same, conducting the pre-heated liquid to a separating chamber, further heating the liquid in'said chamber to effect the substantially constant evaporation oi adefinite percentage of the "liquid, and

1 maintaining the vapors and gases released by i said closed heater.

said eva oration out of contact with the preheated quid at the temperature at which it is conducted to the separating chamber.

19 In the method of treating liquid to effeet the removal of air therefrom, the steps said liquid at the temperature at which it leaves said pre-heating means.

' 20. Water heating and deaerating' apparatus'comprising in combination a deaeratmg chamber having an upper water inlet from which heated water passes through the upper chamber in divided form, a closed heater comprising steam containing tubes below said upper chamber for boiling the water in'contact therewith, a closed water heater external to said chamber comprising a steam space traversed by tubesand means for passing the water treated to said chamber inlet through the last'mentioned tubes, whereby the water is initially heated in said external heater and, subsequently further heated by the tubes of said firstmentioned heater andmeans for withdraw ing air from said chamber independently of 21. Water heating and deaerating apparatus comprising in combination a deaei'ating chamber having an upper water inlet from which heated water passes through the upper chamber in divided form,- a closed heatercomprising steam containing tubes 'below said upper chamber for boiling the water in contact'therewith. and a closed water heater external to said chamber comprising a steam space traversed by tubes, means for passing the water treated to said chamber inlet through the last mentioned tubes, whereby the water is initially heated in said external heater and subsequently further heated by the tubes of said first mentioned heater, an air ofitake from said apparatus, and heat recovery means cooperatmgwith said air ofitakes for heating the'water during its passageto said external heater.

22. Water heating and deaerating apparatus comprising in combinationa deareating chamberhaving an upper water inletvfrom which heated water passes through the upper chamberin divided form, a closed heater comprising steam containing tubes below said upper chamber for boiling the water incontact therewith, and a closed water heater external to said chamber comprising a steam space traversed by tubes, means for passing the water treated to said chamber inlet through the last mentioned tubes, whereby the water is initially heated in said external heater and subsequently further'heated by the tubes of said first me'ntioned heater, an air oiltake from said apparatus and heat refiovery means cooperating with said air ofita e. i

23. Water heating and deaerating apparaus comprising'in combination a deaerating chamber containing a steam space and having a water inlet and meansfor passing the water from said inlet through said steam-space in divided form, a closed heater comprising steam containing tubes within said chamber ing into said chain 1' through said inlet and thereby supplying steam to said steam space, a closed water heater external to said chamber comprising a steam space traversed by, tubes,- means for passing the water treated to saidchamber inlet through said last mentioned tubes whereby the water is initially heated by said external heater and later by said first mentioned tubes and means for withdrawing air from said chamber independently ofsaid closed heater.

24.'Inthe method of treating liquid to eifect the removal of air therefrom and the production of deaerated water, the steps consistin in supplying liquid to a heating means to pre eat the same, conducting the preheated liquid to a separatingchamber', further heating theliquid in said chamber to effect the substantially constant evaporation of a definite percentage of the liquid, and "withdraw ing vapors and gases away from said liquid at a point where the solubility. of the gases in the liquid'i's at a minimum.

25. In themethod of treating liquid to eflect the removal of air therefrom and theproduction of deaerated water, the steps con-' for evaporating a ortion of the water pass-.

sisting'in supplying liquid to a heating means tof preheat the same, conducting the pro- .my hand.

heated liquid to a separating chamber, further heating the li uid in said chamber to effect the substantia 1y constant evaporation of a definite percent e of the liquid, and venting the vapors an gases released within the evaporating chamber from said cham her at a point where the solubility of the gases inthe liquid is at a minimum.

In testimony whereof I have hereunto set WILLIAM s. ELLIOTT. 

